#include <REGX52.H>

void Delay(unsigned int xms )
{
	unsigned char i,j;
	while (xms)
	{
	i = 2;
	j = 239;
	do
	{
		while (--j);
	}while (--i);
	xms--;
	}
}

void main ()
{
	while (1)
	{
//		P2_0 = 0;
//		Delay(500);
//		
//		P2_0 = 1;
//		Delay(500);
		
		if (P3_1 == 0)
		{
			Delay(20);
			while(P3_1==0)
			{
			}
		Delay(20);
		P2_0 = ~P2_0;		
		}
	}
}